A number of edible products found on the market today contain or are comprised of flour-based foodstuffs. Such foodstuffs exist as breads, pizza dough, and bakery goods, but also include coatings and breading for meat, vegetable and fruit products. Foodstuffs employed as coatings and breading are used in part to carry additional flavoring to the coated food product as well as to impart a desirable mouth feel and retain moisture. It is desirable that the flour-based foodstuffs have a texture which is firm, and yet flaky or crunchy depending on the intended application. Flour-based foodstuffs which are dense, watery, limp, or tough are considered unappetizing by the consumer and are thus commercially unacceptable. Typically, a flaky or crunchy texture in a flour-based foodstuff is formed by the addition of components, such as butter, shortening and other fat based materials into the flour-based foodstuffs. The result is that the uncooked dense flour-based foodstuff in the presence of convection cooking heat expands and dries to form discrete layers of flour-based material and thus creates a flaky or crunchy texture.
The problem of creating a flaky or crunchy texture in a flour-based foodstuff using a microwave oven is more difficult to solve. In contrast to a typical convection-type oven, the heat for cooking in a microwave oven is generated inside the flour-based foodstuff rather than above the surface of the food-stuff. Heat is supplied to the entire volume of the flour-based foodstuff in a microwave oven rather than having the heat being applied only at the surface using the convection oven. Heating in the microwave is thus more uniform, and the temperature needed to cook is consequently lower, typically not exceeding the boiling point of water which is 212.degree. F. (100.degree. C.). The flaky or crunchy baked flour products formed in the convection oven by application of relatively high heat and evaporation of water do not form in a microwave oven. Rather, a flour-based foodstuff designed for heating in a convection oven will result in the formation of a mushy, pasty, unappetizing product when heated in a microwave oven.
This problem of formation of an unappetizing cooked flour-based foodstuff becomes more difficult to remedy when an aqueous flour-based foodstuff is to be frozen and then thawed before cooking. One reason for the problem is that the water in the foodstuff is somehow chemically or physically sorbed into the flour-based component on storage. Further, the operation of freezing a flour-based foodstuff containing water causes the liquid water to form ice crystals having a larger volume than the water itself. Upon thawing and cooking, the ability of the foodstuff to form the flaky and crunchy texture is even further diminished. Presently available flour compositions are incapable of forming upon microwaving a flaky or crunchy texture.
It is known with reference to Yamamoto U.S. Pat. No. 3,840,676 to use a combination of zein and prolamine to coat the surface of a foodstuff, such as partially baked bread, for the purpose of binding the foodstuff and protecting it against oxidation and putrefication. When combined, the amino acid and prolamine undergo a gelation reaction and thus form a film on the surface of the coated foodstuff. Yamamoto claimed the process improved the color and luster of the bread surface and also decreased water loss from the bread.